Three-dimensional depth sensor

ABSTRACT

A three-dimensional (3D) depth sensor may include: a plurality of light sources configured to irradiate light to an object, the light having different center wavelengths; an optical shutter configured to allow reflected light reflected from the object to pass through; and an image sensor configured to filter the reflected light having passed through the optical shutter and detect the filtered light.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims priority from Chinese Patent Application No.201611102223.4, filed on Dec. 2, 2016, in the State IntellectualProperty Office (SIPO) of the People's Republic of China and KoreanPatent Application No. 10-2017-0010679, filed on Jan. 23, 2017, in theKorean Intellectual Property Office, the disclosures of which areincorporated herein in their entireties by reference.

BACKGROUND 1. Field

The present disclosure relates to a three-dimensional (3D) depth sensorincluding an optical shutter.

2. Description of the Related Art

Research is underway on various three-dimensional (3D) image acquisitionapparatuses for use by a lay person to produce 3D content, as 3D displayapparatuses have become more prevalent and a demand thereof hasincreased. For example, an increasing amount of research has beenconducted on 3D cameras, motion capture sensors, laser radars (LADARs),etc., which can acquire spatial information about a distant object.

A 3D depth sensor or a depth camera including an optical shutter may bea sensor using a time-of-flight (TOF) method. The TOF method measures aflight time of light reflected from an object and received by a sensorafter having been irradiated to the object. Via the TOF method, the 3Ddepth sensor may measure the distance to an object by measuring the timeof light reflected from the object and returned after having beenirradiated from a light source.

The 3D depth sensor may be used in various areas. It may be used as ageneral motion capture sensor and as a camera for detecting depthinformation in various industrial areas.

SUMMARY

One or more exemplary embodiments provide a three-dimensional (3D) depthsensor which includes a plurality of light sources and measures distanceinformation to an object by forming an optical shutter and an opticalfilter, through which light reflected from the object passes, incorrespondence with the light sources.

Additional aspects will be set forth in part in the description whichfollows and, in part, will be apparent from the description, or may belearned by practice of the presented embodiments.

According to an aspect of an embodiment, a three-dimensional (3D) depthsensor may include: a plurality of light sources configured to irradiatelight to an object, the light having different center wavelengths; anoptical shutter configured to allow reflected light reflected from theobject to pass through; and an image sensor configured to filter thereflected light having passed through the optical shutter and detect thefiltered light.

The plurality of light sources may include a first light source, asecond light source, and a third light source, and the first throughthird light sources may be configured to substantially simultaneouslyirradiate the light having the different center wavelengths.

Differences between the different center wavelengths of the lightirradiated from the first through third light sources may be between 10nm and 1,000 nm.

The different center wavelengths of the light irradiated from the firstthrough third light sources may be between 800-900 nm, between 900-1,000nm, and between 1,000-1,100 nm, respectively.

The optical shutter may include areas configured to respectively allowthe reflected light having the different center wavelengths to passthrough, the light having been irradiated from the plurality of lightsources and reflected from the object.

The plurality of light sources may include a first light source, asecond light source, and a third light source which are configured torespectively irradiate the light having the different centerwavelengths, and the optical shutter may include a first area, a secondarea, and a third area which are respectively configured to allow lighthaving different wavelengths to pass through, the different wavelengthscorresponding to the different center wavelengths of the lightirradiated from the first through third light sources.

The first through third areas of the optical shutter may each have asame shape based on a surface of the optical shutter on which thereflected light is incident.

The first through third areas have a substantially same area size aseach other.

The first through third areas of the optical shutter may have differentshapes from each other based on a surface of the optical shutter onwhich the reflected light is incident.

The first area may have a circular shape, the second area may have afirst ring shape surrounding the first area, and the third area may havea second ring shape surrounding the second area.

The plurality of light sources may be configured to control intensityand a center wavelength of the light irradiated therefrom based on amagnitude of a driving voltage.

The 3D depth sensor may further include a controller configured tocontrol the plurality of light sources, the optical shutter, and theimage sensor.

BRIEF DESCRIPTION OF THE DRAWINGS

The above and/or other aspects will become apparent and more readilyappreciated from the following description of exemplary embodiments,taken in conjunction with the accompanying drawings in which:

FIG. 1 illustrates a configuration diagram of a three-dimensional (3D)depth sensor and graphs of phases of frequencies used for driving the 3Ddepth sensor, according to an exemplary embodiment;

FIG. 2 is a flowchart of a method of driving the 3D depth sensor,according to an exemplary embodiment;

FIG. 3 is a diagram of an example of an optical shutter of the 3D depthsensor, according to an exemplary embodiment;

FIG. 4 is a graph of transmittance with respect to wavelengths ofincident light of the optical shutter of the 3D depth sensor, accordingto an exemplary embodiment;

FIGS. 5A through 5C are diagrams illustrating light that enters theoptical shutter of the 3D depth sensor and is incident on an imagesensor after having passed through the optical shutter, according to anexemplary embodiment;

FIGS. 6A through 6C illustrate various examples of the optical shutterof the 3D depth sensor, according to an exemplary embodiment; and

FIG. 7 is a diagram of an example of the image sensor including anoptical filter of the 3D depth sensor, according to an exemplaryembodiment.

DETAILED DESCRIPTION

Reference will now be made in detail to embodiments, examples of whichare illustrated in the accompanying drawings, wherein like referencenumerals refer to like elements throughout. In this regard, the presentembodiments may have different forms and should not be construed asbeing limited to the descriptions set forth herein. Accordingly, theembodiments are merely described below, by referring to the figures, toexplain aspects. As used herein, the term “and/or” includes any and allcombinations of one or more of the associated listed items.

While this disclosure has been particularly shown and described withreference to exemplary embodiments thereof, it will be understood bythose of ordinary skill in the art that various changes in form anddetails may be made therein without departing from the spirit and scopeof the inventive concept as defined by the appended claims. Theexemplary embodiments should be considered in a descriptive sense onlyand not for purposes of limitation. Therefore, the scope of theinventive concept is defined not by the detailed description of theinventive concept but by the appended claims, and all differences withinthe scope will be construed as being included in the inventive concept.

FIG. 1 illustrates a diagram of a three-dimensional (3D) depth sensor100 and graphs of phases of frequencies used for driving the 3D depthsensor 100, according to an exemplary embodiment.

Referring to FIG. 1, the 3D depth sensor 100 may irradiate light to anobject or subject 200 and may include a light source 10 irradiatinglight having different center wavelengths. The light source 10 mayinclude a plurality of light sources such as a first light source 11, asecond light source 12, and a third light source 13. The first throughthird light sources 11 through 13 may respectively irradiate lighthaving different center wavelengths and may simultaneously irradiatelight to the object 200. The light irradiated from the light source 10to the object 200 may be reflected from the object 200. In addition, the3D depth sensor 100 may include a lens 20 receiving light reflected fromthe object 200, an optical shutter 30, and an image sensor 40.

The light source 10 may include a plurality of individual light sourcesand may include a light-emitting diode (LED) and/or a laser diode (LD).The light source 10 may irradiate to the object 200 light havingwavelengths in a range of infrared (IR) rays or near IR rays. Intensityand a wavelength of light irradiated from the light source 10 may becontrolled by adjusting a magnitude of a driving voltage of the lightsource 10. The light source 10 may include a plurality of individuallight sources, such as three light sources 11, 12, and 13 as illustratedin FIG. 1.

The first through third light sources 11 through 13 included in thelight source 10 may respectively irradiate light having different centerwavelengths to the object 200. For example, the first light source 11may irradiate light having a center wavelength of about 850 nm (e.g.,800-900 nm), the second light source 12 may irradiate light having acenter wavelength of about 950 nm (e.g., 900-1,000 nm), and the thirdlight source 13 may irradiate light having a center wavelength of about1050 nm (e.g., 1,000-1,100 nm) to the object 200. However, respectiveranges of the center wavelengths of light irradiated from the firstthrough third light sources 11 through 13 are not limited thereto.Differences between the center wavelengths of light irradiated from thefirst through third light sources 11 through 13 may be dozens tohundreds of nanometers (e.g., 10-1000 nm). As described above, theintensity and the center wavelengths of light irradiated from the firstthrough third light sources 11 through 13 may be controlled inaccordance with the magnitude of the driving voltage applied to thefirst through third light sources 11 through 13.

The light irradiated from the light source 10 may be reflected from asurface of the object 200. For example, respective light irradiated fromthe first through third light sources 11 through 13 may be reflectedfrom surfaces of clothes or skin of the object 200. Light havingdifferent center wavelengths irradiated from the first through thirdlight sources 11 through 13 may be simultaneously irradiated on theobject 200. Depending on a distance between the light source 10 and theobject 200, phase differences may occur between the light irradiatedfrom the first through third light sources 11 through 13 and the lightreflected from the object 200.

Respective rays of light irradiated from the first through third lightsources 11 through 13 may be reflected from the object 200, and thelight reflected from the object 200 may pass through the lens 20 and beincident on the optical shutter 30. The lens 20 may include atransparent material and condense the light reflected from the object200. In addition, the light condensed by the lens 20 may be transmittedto the optical shutter 30 and the image sensor 40. The optical shutter30 may be arranged with the lens 20 on a path in which the lightirradiated from the first through third light sources 11 through 13 isreflected from the object 200 and proceeds. The optical shutter 30 maychange transmittance and a waveform of the reflected light. The opticalshutter 30 may change a level of the transmittance of the lightreflected from the object 200 and modulate the waveform of the lightreflected from the object 200. The light irradiated from the firstthrough third light sources 11 through 13 may be modulated by applying acertain frequency and the optical shutter 30 may be driven by afrequency that is the same as the certain frequency. A form of thereflected light modulated by the optical shutter 30 may change inaccordance with the phase of light incident on the optical shutter 30.

In FIG. 1, graphs illustrate profiles of intensity changes over time oflight irradiated from the light source 10 including the first throughthird light sources 11 through 13 to the object 200, an intensity changeover time of the light reflected from the object 200, and a change overtime of transmittance of light by the optical shutter 30.

The image sensor 40 of the 3D depth sensor 100 may include various kindsof image detecting sensors. For example, the image sensor 40 may includea complementary metal oxide semiconductor (CMOS) image sensor or acharge coupled device (CCD). However, the present disclosure is notlimited thereto. In addition, the image sensor 40 may include a colorfilter.**

In addition, a controller 50 may be located outside the light source 10including the first through third light sources 11 through 13, theoptical shutter 30, and the image sensor 40 of the 3D depth sensor 100,according to the present disclosure. The controller 50 may calculate aphase of light that has been reflected from the object 200, detected andmeasured by the image sensor 40, and calculate depth information (i.e.,distance information) of the object 200. In addition, the controller 50may display the depth information of the object 200 on a display unit 60for visual presentation to a user. Together with the controller 50 andthe display unit 60, the 3D depth sensor 100 according to the presentdisclosure may constitute a 3D depth sensing system. In addition, the 3Ddepth sensor 100 according to the present disclosure may be used invarious electronic devices, controlled by a controller of an electronicdevice, and may display the depth information of the object 200 via adisplay of an electronic device. The controller 50 may be a processor,such as a central processing unit (CPU), an application-specificintegrated circuit (ASIC), and a system on chip (SoC).

FIG. 2 is a flowchart of a method of driving the 3D depth sensor 100,according to an exemplary embodiment.

Referring to FIGS. 1 and 2, the first through third light sources 11through 13 may simultaneously irradiate light having different centerwavelengths, respectively, to the object 200 (S110). Respective rays oflight irradiated from the first through third light sources 11 through13 may have different center wavelengths from each other and differentphases from each other.

Respective rays of light irradiated from the first through third lightsources 11 through 13 and reflected from the object 200 mayindependently pass through the lens 20 and the optical shutter 30(S120). In FIG. 1, the transmittance of the optical shutter 30 isillustrated as changing over time. In addition, the transmittance of theoptical shutter 30 may change depending on the level of a bias voltageapplied to the optical shutter 30 in a particular wavelength range.Accordingly, the reflected light reflected from the object 200 may havea waveform thereof modulated while passing through the optical shutter30. The modulated waveform of the reflected light may depend on phasesof the reflected light and the transmittance change of the opticalshutter 30 over time. Light that has passed through the optical shutter30 may be detected by the image sensor 40 (S130). The image sensor 40may detect phase differences between the reflected light and theirradiated light irradiated from the first through third light sources11 through 13 by detecting the reflected light that has been modulatedby the optical shutter 30.

The waveform change of the reflected light reflected from the object 200may depend on phases of the reflected light and the transmittance changeover time of the optical shutter 30. As a result, the controller 50 mayobtain the depth information (i.e., distance information) of the object200 (S140) by controlling the transmittance of the optical shutter 30and correcting the depth information of the object 200 that has beenobtained, in accordance with driving characteristics of the opticalshutter 30.

FIG. 3 is a diagram of an example of the optical shutter 30 of the 3Ddepth sensor 100, according to an exemplary embodiment.

Referring to FIGS. 1 and 3, respective rays of light irradiated from thefirst through third light sources 11 through 13 of the 3D depth sensor100 may be reflected from the object 200 and the light reflected fromthe object 200 may pass through the lens 20 and be incident on theoptical shutter 30. The optical shutter 30 may include a first area 31a, a second area 31 b, and a third area 31 c corresponding to thereflected rays of light respectively irradiated from the first throughthird light sources 11 through 13, reflected from the object 200, andincident on the optical shutter 30. The first through third areas 31 athrough 31 c of the optical shutter 30 may change the transmittance andthe waveforms of the reflected light. The optical shutter 30 maymodulate the waveforms of the light reflected from the object 200 byvarying levels of transmittance of the light reflected from the object200. The reflected light irradiated from the first through third lightsources 11 through 13 to the object 200 and reflected from the object200 may be modulated by applying a certain frequency thereto, and theoptical shutter 30 may be driven by a frequency that is the same as thecertain frequency. The shape of the reflected light modulated by theoptical shutter 30 may change in accordance with the phase of the lightincident on the optical shutter 30.

Information about at least three forms of light having different phaseinformation may be needed to obtain the distance information regardingthe object 200. To this end, the 3D depth sensor 100 according to thepresent disclosure may use the first through third light sources 11through 13 respectively having different center wavelengths. Inaddition, the optical shutter 30 may include the first through thirdareas 31 a through 31 c so as to correspond to respective wavelengths oflight irradiated from the first through third light sources 11 through13. In the case when the light source 10 includes three individual lightsources, that is, the first through third light sources 11 through 13,the optical shutter 30 may include three areas such as the first throughthird areas 31 a through 31 c. The first area 31 a of the opticalshutter 30 may have a narrow bandwidth around the center wavelength oflight irradiated from the first light source 11. The second area 31 b ofthe optical shutter 30 may have a narrow bandwidth around the centerwavelength of light irradiated from the second light source 12. Inaddition, the third area 31 c of the optical shutter 30 may have anarrow bandwidth around the center wavelength of light irradiated fromthe third light source 13. In the case when the first through thirdlight sources 11 through 13 of the light source 10 respectivelyirradiate light having the center wavelengths of about 850 nm (e.g.,800-900 nm), about 950 nm (e.g., 900-1,000 nm), and about 1050 nm (e.g.,1,000-1,100 nm), the centers of the bandwidths of the first throughthird areas 31 a through 31 c of the optical shutter 30 may berespectively about 850 nm, about 950 nm, and about 1050 nm as shown inFIG. 4.

FIGS. 5A through 5C are diagrams illustrating light entering the opticalshutter 30 of the 3D depth sensor 100 and incident on an image sensor 40after having passed through the optical shutter 30, according to thepresent disclosure.

Referring to FIGS. 1 and 5 a through 5 c, light respectively irradiatedfrom the first through third light sources 11 through 13 of the lightsource 10 of the 3D depth sensor 100 may be reflected from the object200, and reflected light L11 reflected from the object 200 may passthrough the lens 20 and be incident on the optical shutter 30, accordingto the present disclosure. The reflected light L11 includes rays oflight having different center wavelengths which have been simultaneouslyirradiated from the first through third light sources 11 through 13 tothe object 200 and reflected from the object 200. The reflected lightL11 may be mixed light having different center wavelengths and/ordifferent phases. In addition, reflected light L21 and L31 in FIGS. 5Band 5C may also be the mixed light.

Referring to FIG. 5A, the reflected light, which has been irradiatedfrom the first light source 11 and reflected from the object 200, amongthe reflected light L11 incident on the optical shutter 30, may passthrough the first area 31 a of the optical shutter 30 and be incident onthe image sensor 40 as incident light L12.

Referring to FIG. 5B, the reflected light, which has been irradiatedfrom the second light source 12 and reflected from the object 200, amongthe reflected light L21 incident on the optical shutter 30, may passthrough the second area 31 b of the optical shutter 30 and be incidenton the image sensor 40 as incident light L22.

In addition, referring to FIG. 5C, the reflected light, which has beenirradiated from the third light source 13 and reflected from the object200, among the reflected light L31 incident on the optical shutter 30,may pass through the third area 31 c of the optical shutter 30 and beincident on the image sensor 40 as incident light L32.

As illustrated in FIGS. 1 and 5A through 5C, according to the presentdisclosure, the distance information about the object 200 may beobtained after the light irradiated from the light source 10, that is,the first through third light sources 11 through 13 of the 3D depthsensor 100, has been reflected from the object 200 and detected by theimage sensor 40. The distance information d regarding the object 200 maybe determined by Formulas 1 and 2 below.

$\begin{matrix}{\varphi_{TOF} = {\tan^{- 1}( {\sqrt{3}\frac{I_{240{^\circ}} - I_{120{^\circ}}}{{2I_{0{^\circ}}} - I_{240{^\circ}} - I_{120{^\circ}}}} )}} & \lbrack {{Formula}\mspace{14mu} 1} \rbrack \\{d = {\frac{c}{4\pi\; f}\varphi_{TOF}}} & \lbrack {{Formula}\mspace{14mu} 2} \rbrack\end{matrix}$

In Formula 1, I₀°, I₁₂₀°, and I₂₄₀° may be intensities of the lightirradiated from the first through third light sources 11 through 13.According to the present disclosure, the 3D depth sensor 100 may be asensor using a time-of-flight (TOF) method, and may measure the distanceinformation about the object 200 via the TOF method.

FIGS. 6A through 6C illustrate various examples of the optical shutter30 of the 3D depth sensor 100, according to an exemplary embodiment.Incident surfaces of the optical shutter 30, on which the reflectedlight reflected from the object 200 in FIG. 1 is incident, areillustrated. According to the present disclosure, the optical shutter 30of the 3D depth sensor 100 may be formed in various configurations. InFIG. 3, the optical shutter 30 is formed in a rectangular shape based ona light incident surface and the first through third areas 31 a through31 c respectively including structures having the same rectangular shapeas each other. However, the embodiment is not limited thereto. Variousconfigurations as illustrated in FIGS. 6A through 6C may be used.

Referring to FIGS. 1 and 6A, the optical shutter 30 of the 3D depthsensor 100 may include a first area 32 a, a second area 32 b, and athird area 32 c, according to the present disclosure. The opticalshutter 30 in FIG. 6A is illustrated having the incident surface of acircular shape on which the reflected light from the object 200 in FIG.1 is incident. The first through third areas 32 a through 32 c may eachhave substantially have the same shape and be respectively formed tohave conical cross-sectional shapes. According to the presentdisclosure, the first through third areas 32 a through 32 c of theoptical shutter 30 of the 3D depth sensor 100 may have substantially thesame area size.

Referring to FIGS. 1 and 6B, the optical shutter 30 of the 3D depthsensor 100 may include a first area 33 a, a second area 33 b, and athird area 33 c, according to the present disclosure. The opticalshutter 30 in FIG. 6B is illustrated having the incident surface of aquadrangular shape on which the reflected light from the object 200 inFIG. 1 is incident. The first through third areas 33 a through 33 c mayhave substantially the same shape and be respectively formed to haverectangular shapes. According to the present disclosure, the firstthrough third areas 33 a through 33 c of the optical shutter 30 of the3D depth sensor 100 may have substantially the same area.

Referring to FIGS. 1 and 6C, the optical shutter 30 may have theincident surface of a circular shape on which the reflected light fromthe object 200 is incident. A first area 34 a, a second area 34 b, and athird area 34 c of the optical shutter 30 may have different shapesand/or sizes from each other. The first area 34 a may be formed to havea circular shape and the second area 34 b may be formed to have a ringshape (e.g., concentric circles) surrounding the circular shape of thefirst area 34 a. In addition, the third area 34 c may be formed to havea ring shape surrounding the ring shape of the second area 34 b. InFIGS. 3 and 6A through 6B, each of the first through third areas of theoptical shutter 30 is illustrated as having substantially the sameshape. However, these are only examples and, as illustrated in FIG. 6C,the first through third areas 34 a through 34 c may have differentshapes from each other. Even though the first through third areas 34 athrough 34 c have different shapes from each other, respective areas ofthe first through third areas 34 a through 34 c may be substantially thesame on the incident surface of the optical shutter 30 on which thereflected light from the object 200 is incident.

FIG. 7 is a diagram of an example of the image sensor 40 of the 3D depthsensor 100, according to an exemplary embodiment. The image sensor 40may include an optical filter.

Referring to FIG. 7, the image sensor 40 of the 3D depth sensor 100 mayinclude a filter layer 41 on a sensor array 45, according to the presentdisclosure. The sensor array 45 may be an array structure including theCMOS image sensor, the CCD, etc. In addition, as illustrated in FIG. 1,the filter layer 40 may include a first area 41 a, a second area 41 b,and a third area 41 c, and each of the first through third areas 41 athrough 41 c may allow only the reflected light to pass throughaccording to respective center wavelengths of light irradiated from thefirst through third light sources 11 through 13 of the light source 10.For example, when the first through third light sources 11 through 13 ofthe light source 10 respectively irradiate light having centerwavelengths of about 850 nm, about 950 nm, and about 1050 nm, the firstarea 41 a of the filter layer 41 may be formed to transmit only light ofabout 850 nm among light having wavelengths of about 850 nm, about 950nm, and about 1050 nm, the second area 41 b of the filter layer 41 maybe formed to transmit only light of about 950 nm among light havingwavelengths of about 850 nm, about 950 nm, and about 1050 nm, and thethird area 41 c of the filter layer 41 may be formed to transmit onlylight of about 1050 nm among light having wavelengths of about 850 nm,about 950 nm, and about 1050 nm.

The 3D depth sensor 100 according to the present disclosure may be usedin various electronic devices and mobile devices, such as a computer, adesktop computer, a laptop computer, a smartphone, a tablet computer, awearable computer, etc. The 3D depth sensor 100 as well as independentelements such as the controller 50 and the display 60 may be used in a3D depth sensor system, along with central processing units and displaysof various electronic devices.

A 3D depth sensor according to the present disclosure may include aplurality of light sources respectively irradiating light havingdifferent center wavelengths, and may reduce motion blur, which mayoccur when a single light source is used, by irradiating light from theplurality of light sources to an object. In addition, image informationabout the object may be obtained at a higher frame rate, and thus, moreaccurate distance information about the object may be obtained.

It should be understood that embodiments described herein should beconsidered in a descriptive sense only and not for purposes oflimitation. Descriptions of features or aspects within each embodimentshould typically be considered as available for other similar featuresor aspects in other embodiments.

While one or more embodiments have been described with reference to thefigures, it will be understood by those of ordinary skill in the artthat various changes in form and details may be made therein withoutdeparting from the spirit and scope as defined by the following claims.

What is claimed is:
 1. A three-dimensional (3D) depth sensor comprising:a plurality of light sources configured to irradiate light to an object,the light having different center wavelengths; an optical shutterconfigured to allow reflected light reflected from the object to passthrough; and an image sensor configured to filter the reflected lighthaving passed through the optical shutter and detect the filtered light,wherein the plurality of light sources are configured to controlintensity and a center wavelength of the light irradiated therefrombased on a magnitude of a driving voltage.
 2. The 3D depth sensor ofclaim 1, wherein the plurality of light sources comprise a first lightsource, a second light source, and a third light source, and the firstthrough third light sources are configured to simultaneously irradiatethe light having the different center wavelengths.
 3. The 3D depthsensor of claim 2, wherein differences between the different centerwavelengths of the light irradiated from the first through third lightsources are between 10 nm and 1,000 nm.
 4. The 3D depth sensor of claim3, wherein the different center wavelengths of the light irradiated fromthe first through third light sources are between 800-900 nm, between900-1,000 nm, and between 1,000-1,100 nm, respectively.
 5. The 3D depthsensor of claim 1, wherein the optical shutter comprises areasconfigured to respectively allow the reflected light having thedifferent center wavelengths to pass through, the light having beenirradiated from the plurality of light sources and reflected from theobject.
 6. The 3D depth sensor of claim 5, wherein the plurality oflight sources comprise a first light source, a second light source, anda third light source which are configured to respectively irradiate thelight having the different center wavelengths, and the optical shuttercomprises a first area, a second area, and a third area which arerespectively configured to allow light having different wavelengths topass through, the different wavelengths corresponding to the differentcenter wavelengths of the light irradiated from the first through thirdlight sources.
 7. The 3D depth sensor of claim 6, wherein the firstthrough third areas of the optical shutter each have a same shape basedon a surface of the optical shutter on which the reflected light isincident.
 8. The 3D depth sensor of claim 7, wherein the first throughthird areas have a substantially same area size as each other.
 9. The 3Ddepth sensor of claim 6, wherein the first through third areas of theoptical shutter have different shapes from each other based on a surfaceof the optical shutter on which the reflected light is incident.
 10. The3D depth sensor of claim 9, wherein the first through third areas have asubstantially same area size as each other.
 11. The 3D depth sensor ofclaim 9, wherein the first area has a circular shape, the second areahas a first ring shape surrounding the first area, and the third areahas a second ring shape surrounding the second area.
 12. The 3D depthsensor of claim 1, further comprising a controller configured to controlthe plurality of light sources, the optical shutter, and the imagesensor.